CN219918645U - Oil-cooled hub motor - Google Patents

Abstract

The utility model discloses an oil-cooled hub motor, which comprises a hub and end covers at two ends of the hub, wherein a containing cavity is defined between the two end covers and the hub, a stator is positioned in the containing cavity, liquid cooling oil is injected into the containing cavity, and the cooling oil has an electric insulation characteristic. The air-permeable valve is arranged on the end cover, the inlet end of the air-permeable valve is positioned in the accommodating cavity, and the outlet end faces the outer side of the hub motor. A ventilation channel is formed between the inlet end and the outlet end in the ventilation valve, a waterproof ventilation film is arranged in the outlet end of the ventilation valve, a plurality of micropores are formed on the waterproof ventilation film, and the micropores define the ventilation channel. An oil-proof structure is arranged in the inner end of the air-permeable valve and extends into the air-permeable channel, and the oil-proof structure is used for stopping the cooling oil from overflowing to the outlet end of the air-permeable valve.

Description

Oil-cooled hub motor

Technical Field

The present utility model relates to a hub motor, and more particularly, to a hub motor having cooling oil injected therein.

Background

The hub motor is used as an integrated driving system of a new energy vehicle and is used as a power source for vehicle running. When a vehicle runs on various different roads, various running conditions are met, frequent starting, accelerating, decelerating, stopping and the like of the vehicle are required, the working condition of the hub motor is complicated, and the temperature inside the hub motor can change greatly. When the vehicle cruises at a high speed, the hub motor needs to provide a higher rotational speed to meet the requirement of the vehicle speed, and when the vehicle runs at a low speed on a long slope, the hub motor needs to provide a larger torque to meet the requirement of climbing. Therefore, the loss of the hub motor is increased under the two conditions, more heat is generated, the temperature of the hub motor is increased, and the change is obvious. Through actual measurement and calculation, the limit temperature difference of the hub motor of the common electric vehicle in the working process can reach about 100 degrees, and the high temperature difference can bring negative influence on windings in the motor on one hand, and can obviously reduce the working efficiency of the motor and improve the energy consumption on the other hand. Most of the existing hub motors adopt an air cooling mode, namely, the heat exchange with external cold air is realized by utilizing the characteristics of metal materials of the motors. But the part of the hub motor, which generates heat, is not in direct contact with the end cover, the heat is transferred through a gas medium, the heat transfer efficiency is poor, and the working efficiency of the cooling mode is relatively low. The oil cooling technology can be directly contacted with the heating component of the motor, so that the motor rotor and the stator are cooled in an immersed mode, and the heat dissipation effect is relatively better. The oil medium has the advantages of good insulativity, no magnetic conduction, low solidifying point, high boiling point and the like.

Chinese patent literature (publication number: CN 218071186U) discloses a sealing oil cooling structure of an inner rotor hub motor core, which relates to the field of hub motors. The technical scheme is characterized by comprising a left half shaft, a right half shaft, a hub shell and a core assembly, wherein the core assembly comprises a core shaft and a core shell, an organic core cavity is formed in the core shell, and an oil storage cavity is formed between the inner side of the hub shell and the outer side of the core shell; the machine core shell comprises a machine core left shell, a wire outlet hole is formed in the machine core left shell, and the left half shaft comprises a fixed plate connected with the outer end face of the machine core left shell; the outer end surface of the fixed plate is provided with a sealing cover plate, and sealing joint surfaces are respectively formed between the sealing cover plate and the fixed plate and the left shell of the movement; the sealing cover plate is used for preventing cooling oil in the oil storage chamber from entering the core chamber through the wire outlet hole.

The sealing oil cooling structure realizes the oil cooling of the hub motor by arranging the oil storage chamber outside the core shell and injecting cooling oil into the oil storage chamber. The related hub motor has relatively large axial dimension, and the cooling efficiency of the hub motor is even lower than that of the common air-cooled hub motor.

Disclosure of Invention

The utility model aims to solve the technical problems that: the oil-cooled hub motor has the advantages of good structural compactness and good heat dissipation effect, and can be well adapted to temperature change in the working process of the motor.

In order to solve the technical problems, the technical scheme of the utility model is as follows: the oil-cooled hub motor comprises a hub and end covers arranged at two ends of the hub in a liquid-tight manner, wherein a containing cavity is defined between the two end covers and the hub, a stator is positioned in the containing cavity, liquid cooling oil is injected into the containing cavity, and the cooling oil has electric insulation characteristics; an oil-proof structure is arranged in the inner end of the ventilation valve and extends into the ventilation channel, and the oil-proof structure is used for stopping cooling oil from overflowing to the outlet end of the ventilation valve.

The outer edge of the end cover is coated with a layer of adhesive, and liquid sealing bonding is realized between the adhesive and the hub. The in-wheel motor being in an installed state refers to a state in which the in-wheel motor is installed to the vehicle, and the in-wheel motor is in a standing state at this time. The cooling oil is usually transformer oil, the injection amount of the cooling oil is not too much, the maximum accumulated liquid amount of the cooling oil refers to that the cooling oil injected into the accommodating cavity flows back to the lower part in the accommodating cavity after working for a period of time (usually taking month as a unit) and is in a static state, the accumulated cooling oil just penetrates through the stator winding at the lower part of the stator winding to reach the inner ring of the stator winding, the liquid level of the cooling oil can be slightly higher than the height of the inner ring of the stator winding or slightly lower than the height of the inner ring of the stator winding, and the height difference between the cooling oil and the cooling oil is usually in the range of a few millimeters. The inner ring of the stator winding is a circle where the inner end of the stator winding is positioned in the radial direction of the hub motor. In a vertically arranged in-wheel motor, the low point of the inner ring of the stator winding corresponds to the maximum liquid accumulation height of the cooling oil. The micropores define ventilation channels, namely the waterproof ventilation membrane is arranged in the ventilation valve in a sealing way, and the micropores in the waterproof ventilation membrane integrally define the ventilation channels.

Further, the inlet end of the ventilation valve is of a split type structure and comprises a base and a connector, a notch is formed in the position of the base on the ventilation valve, the connector is buckled in the notch, a buckling surface between the connector and the notch is located in the axial direction of the ventilation valve, the oil-proof structure is of a split type structure, and the oil-proof structure is arranged on the connector and the base in a split type. The inlet end of the ventilation valve is of a split type structure, so that a relatively complex oil-proof structure can be arranged in the inlet end of the ventilation valve in a molded mode, and cooling oil can be effectively prevented from entering the ventilation valve from the inlet end of the ventilation valve.

Further, the oil-proof structure comprises a plurality of inclined plates arranged in the ventilation valve, the inner ends of the inclined plates are connected with the inner wall surface of the ventilation valve into a whole, and the outer ends of the inclined plates incline towards the inlet end of the ventilation valve. The arrangement of the inclined plate structure is beneficial to the cooling oil entering the air permeable valve to flow into the containing cavity along the trend of the inclined plate.

Further, the sloping plate on the base and the sloping plate on the connector are respectively and correspondingly arranged. After the connecting body is buckled on the base, the inclined plates on the connecting body and the base are spliced into large inclined plates respectively, so that the oil guiding efficiency of the inclined plates can be effectively ensured.

Further, the oil-proof structure comprises a plurality of spacing rings arranged in the ventilation valve, the end face of each spacing ring, facing the inlet end of the ventilation valve, is a concave cambered surface, and the positions of the spacing rings on the base and the connecting body are in one-to-one correspondence. The spacer ring structure also facilitates the backflow of cooling oil entering the breather valve from the inlet end into the accommodating cavity.

Further, in the ventilation valve, a baffle ring is arranged between two adjacent baffle rings, and two axial end faces of the baffle ring are planes. The baffle ring is arranged, so that cooling oil can be effectively prevented from excessively penetrating into the ventilation valve.

Further, the outlet end of the ventilation valve is provided with a pressing cap, one end of the pressing cap is closed, the other end of the pressing cap is opened, the opening end of the pressing cap is used for pressing the waterproof ventilation film on the outlet end of the ventilation valve, and the pressing cap is provided with a through hole. The pressure cap can effectively realize the crimping to waterproof ventilated membrane, and the setting of pressure cap also can provide certain guard action to waterproof ventilated membrane.

Further, a coupling ring is formed at the outlet end of the ventilation valve, the pressing cap is arranged in the coupling ring, the waterproof ventilation film is pressed on the bottom surface of the coupling ring, the through holes are formed in the side wall of the pressing cap, a gap is formed between the side wall of the pressing cap and the inner wall surface of the coupling ring, and the through holes are located in the depth range of the coupling ring. This makes external muddy water be difficult for entering into the position department of waterproof ventilated membrane from the exit end of ventilative valve, can effectively guarantee ventilative passageway's smoothness nature.

Further, the number of the through holes is four, the four through holes are arranged on the pressing cap in a cross shape, and the cross sections of the through holes are rectangular. The through holes are arranged in the way that the dustproof effect inside the press cap is good.

Further, the press cap is in a convex shape, the connecting ring is matched with the press cap, an annular limiting groove is formed in the inner wall surface of the connecting ring, a protruding convex ring is arranged on the outer peripheral surface of the press cap, and the convex ring is clamped in the limiting groove in an anastomotic manner. The fit form between the press cap and the connecting ring is combined with the existence of the through holes, so that the press cap can be conveniently taken out from the connecting ring, and the waterproof permeable membrane can be conveniently replaced.

Compared with the prior art, the utility model has the beneficial effects that: the cooling oil can be directly injected into the accommodating cavity of the hub motor, so that the cooling oil is directly and fully contacted with the heating source stator core and the stator winding in the motor, the fluidity of the cooling oil and the characteristic of oil point splashing can conduct heat to the end cover, and the heat is efficiently conducted to the outside, so that the motor works in an ideal temperature interval. The injection amount of the cooling oil also ensures that the existence of the cooling oil does not generate a large retarding effect on the movement of the motor, but can provide a good lubricating effect on the relative movement inside the motor.

Through the setting of ventilation valve to and set up in the ventilation valve waterproof ventilated membrane, in the course of the work, hold the pressure in the chamber and can not produce great change because of the change of in-wheel motor operating mode, hold the pressure in the chamber and external pressure unanimous basically, the sealing requirement of in-wheel motor is low. The setting of grease proofing structure under the prerequisite of conveniently filling into cooling oil in holding the intracavity, can also prevent that cooling oil from spilling over the outside to in-wheel motor.

Drawings

Fig. 1 is a front view of the related in-wheel motor.

Fig. 2 is an axial cross-sectional view of fig. 1.

Fig. 3 is a schematic diagram of the cooling oil injection amount.

Fig. 4 is a structural view of the ventilation valve.

FIG. 5 is an axial cross-sectional view of one embodiment of a breather valve in one direction.

FIG. 6 is an axial cross-sectional view of an embodiment of a breather valve in another direction.

Fig. 7 is an axial cross-sectional view of another embodiment of a breather valve.

Fig. 8 is a structural view of the connector.

Fig. 9 is a perspective view of the ventilation valve.

In the figure, 1, an end cover; 2. a hub; 3. a wheel axle; 4. a ventilation valve; 41. a coupling ring; 42. a waterproof breathable film; 43. pressing the cap; 44. a through hole; 45. a base; 46. a sloping plate; 47. a connecting body; 48. a spacer ring; 49. a baffle ring; 5. a stator winding; 51. an inner ring; 6. cooling oil; 7. a seal ring; 8. and a gasket.

Detailed Description

With reference to the drawings, the oil-cooled hub motor is applied to a vehicle, and structurally comprises a circular hub 2, and a tire is arranged on the periphery of the hub 2. With reference to fig. 1 and 2, end caps 1 are respectively arranged at two ends of the hub 2, the end caps 1 are disc-shaped, and liquid sealing is realized between the end caps 1 and the hub 2 in the form of viscose.

An accommodating cavity is defined between the two end covers 1 and the hub 2, the stator is positioned in the accommodating cavity, and liquid cooling oil 6 is injected into the accommodating cavity. The cooling oil 6 has an electrical insulation property, and is typically transformer oil, or may be lubricating oil. The wheel axle 3 is connected with the axial position of the end cover 1 in a penetrating way, a bearing is arranged between the end cover 1 and the wheel axle 3, and the wheel axle 3 is rotatably supported on the end cover 1 through the bearing. An oil seal is also sleeved between the end cover 1 and the wheel axle 3 so as to prevent cooling oil 6 from seeping to the outside from the positions of the wheel hub 2 and the wheel axle 3.

The end cover 1 is provided with a through mounting hole which is arranged along the axial direction of the hub 2. The inside of the mounting hole is provided with a ventilation valve 4, the ventilation valve 4 is cylindrical, and the ventilation valve 4 is horizontally arranged on the axial direction of the hub 2. The mounting hole is internally provided with internal threads, the outer peripheral surface of the ventilation valve 4 is provided with external threads, and the ventilation valve 4 is in threaded connection with the mounting hole. In order to ensure the tightness of the mounting hole, a sealing ring 7 is sleeved on the air-permeable valve 4, and the sealing ring 7 is elastically deformed between the air-permeable valve 4 and the end cover 1. The inlet end of the ventilation valve 4 extends into the accommodating cavity, and the outlet end faces the outer side of the hub motor. A ventilation channel is formed between the inlet end and the outlet end in the ventilation valve 4, the gas pressure in the accommodating cavity is increased due to high temperature, and a part of gas enters the ventilation valve 4 from the inlet end and is discharged to the outside from the outlet end, so that the internal pressure and the external pressure of the accommodating cavity are balanced. Of course, the direction of the gas flow may also be reversed to compensate for the low pressure in the receiving chamber.

Referring to fig. 3, in the in-wheel motor mounted state, that is, in the in-wheel motor vertical state, the maximum liquid accumulation height of the cooling oil 6 corresponds to the height at the low point of the inner ring 51 of the stator winding 5. In fig. 3 it is shown that the maximum liquid level of the cooling oil 6 is slightly higher than the level at the low point of the inner ring 51 of the stator winding 5, the height relationship between them may also be equal or slightly smaller.

The outlet end of the ventilation valve 4 is internally provided with a waterproof ventilation film 42, a plurality of micropores are formed on the waterproof ventilation film 42, the pore diameter of the micropores is 0.2-1.0 mu m, and the pore diameter of the micropores is one ten thousandth of that of common water drops but is 6 times and 700 times larger than that of water vapor molecules. The micropores define ventilation channels through which gas flows as it passes through the waterproof and breathable membrane 42. However, under the influence of the surface tension of the liquid, the micropores can stop external water from entering the accommodating cavity. Such a waterproof breathable membrane 42 is generally commercially available as a conventional nylon waterproof breathable membrane. GORE-TEX waterproof breathable fabric produced by W L GORE company in the United states can be used as a better waterproof breathable film.

The inner end of the ventilation valve 4 is also internally provided with an oil-proof structure, the oil-proof structure is a mechanical structure, the oil-proof structure stretches into the intercepting surface of the ventilation channel, and the oil-proof structure is combined with the movement of the wheel in the working process, so that even if cooling oil 6 entering the ventilation valve 4 exists, the cooling oil 6 can be thrown out into the accommodating cavity, and the oil-proof structure can effectively stop the overflow of the cooling oil 6 to the outlet end of the ventilation valve 4.

Because the oil-proof structure is relatively complex and is positioned in the air-permeable valve 4, the oil-proof structure is formed conveniently. The inlet end of the breather valve 4 is now provided as a split structure comprising a base 45 and a connector 47. A notch is formed in the ventilation valve 4 at the position of the base 45, and the connector 47 is engaged with the notch. This corresponds to the cylindrical inlet end of the breather valve 4 being partially cut off in the axial direction, and the base 45 and the connecting body 47 are formed. The engagement surface between the connector 47 and the notch is located in the axial direction of the ventilation valve 4. Corresponding to the split structure of the inlet end of the ventilation valve 4, the oil-proof structure is also a split structure, and the oil-proof structure is formed on the connector 47 and the base 45 separately. After the connector 47 is snapped into the notch, the connector 47 and the oil-repellent structure on the base 45 are correspondingly formed as a whole. In order to facilitate the connection in place, bayonets and chucks are respectively arranged at corresponding positions of the two wall bodies of the base 45 and the connecting body 47, and the quick connection in place of the connecting body 47 is realized by inserting the chucks into the bayonets. On the bonding surface where the connector 47 and the base 45 are bonded, the connector 47 is firmly connected to the base 45 by applying adhesive.

As an embodiment, referring to fig. 5 and 6, the oil-proof structure includes a plurality of inclined plates 46 disposed in the ventilation valve 4, wherein inner ends of the inclined plates 46 are integrally connected with an inner wall surface of the ventilation valve 4, and outer ends of the inclined plates 46 incline toward an inlet end of the ventilation valve 4. The inclined plate 46 on the base 45 and the inclined plate 46 on the connecting body 47 are respectively provided correspondingly, and when the connecting body 47 is fastened to the base 45, the connecting body 47 and the inclined plate 46 on the base 45 are respectively connected as a whole correspondingly. After some cooling oil 6 enters the inlet end of the ventilation valve 4, the ventilation valve 4 moves along with the end cover 1, the cooling oil 6 entering the ventilation valve 4 can flow back into the accommodating cavity under the action of centrifugal force, and the outer surface of the inclined plate is obliquely arranged, so that the cooling oil 6 in the ventilation valve 4 can be promoted to flow to the inlet end of the ventilation valve 4. In fig. 5, the ventilation valve 4 has two sets of inclined plates, and the two sets of inclined plates are respectively located on two opposite inner wall surfaces in the ventilation valve 4. In the axial direction of the ventilation valve 4, two groups of inclined sheets are arranged at intervals. Part of the inclined sheets are inserted into the interval between two adjacent inclined sheets in the opposite group, so that an oil-proof structure for promoting the cooling oil 6 to flow towards the inlet end of the ventilation valve 4 is formed.

As another embodiment, referring to fig. 7 and 8, the oil-proof structure includes a plurality of spacers 48 disposed in the ventilation valve 4, the end faces of the spacers 48 facing the inlet end of the ventilation valve 4 are concave cambered surfaces, the positions of the spacers 48 on the base 45 and the connecting body 47 are in one-to-one correspondence, and the two end faces of the base 45 and the connecting body 47 are corresponding, so that after the connecting body 47 is fastened to the base 45, a plurality of integral spacers 48 are formed in the inlet end of the ventilation valve 4. In the breather valve 4, a baffle ring 49 is arranged between two adjacent spacing rings 48, and two axial end faces of the baffle ring 49 are planes.

Referring to fig. 9, the outlet end of the ventilation valve 4 is provided with a press cap 43, one end of the press cap 43 is closed, and the other end is open. The open end of the cap 43 is connected to the ventilation valve 4, and the waterproof ventilation membrane 42 is crimped on the outlet end of the ventilation valve 4. The press cap 43 is provided with a through hole 44, and the through hole 44 also defines the ventilation channel.

Referring to fig. 5, 7 and 8, a coupling ring 41 is formed at the outlet end of the breather valve 4, and the press cap 43 is disposed in the coupling ring 41. The coupling ring 41 is of expanded diameter with respect to the body of the ventilation valve 4, so that an annular shoulder is formed between the coupling ring 41 and the body of the ventilation valve 4, the end face of the shoulder acting as the bottom face of the coupling ring 41, on which shoulder the waterproof ventilation membrane 42 is supported. A gasket 8 is provided on the waterproof and breathable membrane 42, a press cap 43 is connected in the coupling ring 41, and the waterproof and breathable membrane 42 is pressed onto the shoulder through the gasket 8. Referring to fig. 9, the through hole 44 is formed on the side wall of the press cap 43, a gap is formed between the side wall of the press cap 43 and the inner wall surface of the coupling ring 41, the through hole 44 is located within the depth range of the coupling ring 41, and the through hole 44 is communicated with the gap. The number of the through holes 44 is four, the four through holes 44 are arranged on the press cap 43 in a cross shape, and the cross section of the through holes 44 is rectangular.

The press cap 43 is in a shape of a "convex" in response to the presence of the shoulder, and the coupling ring 41 is adapted to the press cap 43. The connection between the coupling ring 41 and the press cap 43 is realized by adopting a clamping manner, specifically, an annular limiting groove is arranged on the inner wall surface of the coupling ring 41, a protruding convex ring is arranged on the outer peripheral surface of the press cap 43, and the convex ring is clamped in the limiting groove in an anastomotic manner.

Claims (10)

1. The oil-cooled hub motor comprises a hub and end covers arranged at two ends of the hub in a liquid-tight manner, wherein a containing cavity is defined between the two end covers and the hub, a stator is positioned in the containing cavity, liquid cooling oil is injected into the containing cavity, and the cooling oil has electric insulation characteristics; an oil-proof structure is arranged in the inner end of the ventilation valve and extends into the ventilation channel, and the oil-proof structure is used for stopping cooling oil from overflowing to the outlet end of the ventilation valve.

2. The oil-cooled hub motor of claim 1, wherein the inlet end of the breather valve is of a split structure and comprises a base and a connector, a notch is formed in the breather valve at the position of the base, the connector is buckled in the notch, a buckling surface between the connector and the notch is located in the axial direction of the breather valve, the oil-proof structure is of a split structure, and the oil-proof structure is arranged on the connector and the base in a split mode.

3. The oil-cooled hub motor of claim 2, wherein the oil-proof structure comprises a plurality of inclined plates arranged in the air-permeable valve, the inner ends of the inclined plates are connected with the inner wall surface of the air-permeable valve into a whole, and the outer ends of the inclined plates incline towards the inlet end of the air-permeable valve.

4. An oil-cooled hub motor as set forth in claim 3 wherein the inclined plate on the base and the inclined plate on the connector are disposed in correspondence, respectively.

5. The oil-cooled hub motor of claim 2, wherein the oil-proof structure comprises a plurality of spacer rings arranged in the air-permeable valve, the end face of the spacer rings facing the inlet end of the air-permeable valve is a concave cambered surface, and the positions of the spacer rings on the base and the connector are in one-to-one correspondence.

6. The oil-cooled hub motor of claim 5, wherein a baffle ring is disposed between two adjacent spacer rings in the air-permeable valve, and two axial end surfaces of the baffle ring are planar.

7. The oil-cooled hub motor of claim 1, wherein the outlet end of the air-permeable valve is provided with a press cap, one end of the press cap is closed, the other end of the press cap is open, the open end of the press cap is used for pressing the waterproof air-permeable membrane onto the outlet end of the air-permeable valve, and the press cap is provided with a through hole.

8. The oil-cooled hub motor of claim 7, wherein a coupling ring is formed at the outlet end of the air-permeable valve, the press cap is disposed in the coupling ring, the waterproof air-permeable membrane is pressed against the bottom surface of the coupling ring, the through hole is disposed on the sidewall of the press cap, a gap is provided between the sidewall of the press cap and the inner wall surface of the coupling ring, and the through hole is located within the depth range of the coupling ring.

9. The oil-cooled hub motor of claim 8, wherein the number of through holes is four, the four through holes are arranged on the press cap in a cross shape, and the cross section of the through holes is rectangular.

10. The oil-cooled hub motor of claim 8, wherein the press cap is in a shape of a Chinese character 'tu', the coupling ring is matched with the press cap, an annular limiting groove is arranged on the inner wall surface of the coupling ring, a protruding convex ring is arranged on the outer peripheral surface of the press cap, and the convex ring is clamped in the limiting groove in an anastomotic manner.